The present invention relates to audio speakers, and more particularly to an improved gasket or speaker ring employed in mounting a speaker assembly to a speaker cabinet.
Audio speakers include, among other things, a vibrating paper cone which generates sound waves in response to electrical signals supplied to the speaker. In order to operate effectively the speaker must be mounted in a way that allows the paper cone to vibrate freely so that sounds may be faithfully reproduced without distortion.
Typically, a speaker will be mounted within a conical support basket. The speaker basket includes a base at the smaller end of the basket for supporting the electrical components of the speaker. Opposite the base, the front or top of the basket forms a circular rim comprising an annular flange extending parallel to the front face of the speaker and extending around the perimeter thereof, and a small lip which extends forward from the flange again, encircling the entire perimeter of the basket. When the speaker is mounted in the basket, the vibrating speaker cone extends from near the base toward the rim of the basket where it is attached to the annular flange.
For attaching the vibrating cone to the flange, a structure known as a roll-over is attached to the outer peripheral edge of the cone. The roll-over may be formed of plastic or some other suitable material, and comprises a transition piece from the conical sidewalls of the vibrating cone to the flat annular surface of the speaker basket rim. In general, the roll-over comprises a first conical surface which is glued or otherwise attached to the vibrating speaker cone, and a second flat annular surface for attaching to the rim of the speaker basket. An arcuate ridge, or a succession of such ridges arranged side-by-side in a corrugated fashion, form the transition from the flat annular surface of the roll-over to the inner conical surface of the rollover, and thus to the speaker cone itself. When the conical surface of the roll-over is joined to the speaker cone and the flat annular surface is glued to the annular rim of the speaker basket, the arcuate ridge or ridges forming the transition section allow the conical surface of the roll-over, as well as the speaker cone itself, to move back and forth axially relative to the rim of the speaker basket. Thus, the roll-over allows the speaker cone to vibrate freely without distortion.
Once the roll-over has been attached to the annular flange, a speaker ring or gasket is inserted around the rim of the basket above the rollover. The speaker ring is typically glued to the flat portion of the roll-over. Prior to gluing, the speaker ring is held in place in the outward radial direction by the short lip extending around the outer edge of the speaker basket rim.
When finally assembled, the speaker basket, speaker, and speaker ring may be mounted to a speaker cabinet. This may be accomplished in one of two ways. First, the outer surface of the speaker ring can be placed flat against a mounting panel of the speaker cabinet, and fasteners such as screws may be inserted through the mounting panel and the speaker basket flange to attach the speaker to the mounting panel. In this arrangement the speaker ring acts to isolate the vibrating cone within the speaker from the mounting panel of the speaker cabinet, thereby limiting distortion to the audio signals broadcast by the speaker. Alternately, the speaker assembly may be dropped into a hole formed in the mounting panel of the speaker cabinet. In this arrangement, the back side of the speaker basket annular flange engages the mounting panel and fasteners may be inserted through the annular flange and the mounting panel to secure the speaker assembly within the cabinet. In this arrangement, the mounting flange and roll-over are visible from the front of the cabinet. Therefore, the speaker ring performs a more aesthetic function by providing a neat trim piece which conceals the annular flange and the glued-in-place roll-over.
Speaker rings are typically supplied in short arcuate segments. During the speaker assembly process the individual segments must be manually placed within the basket rim and glued to the upper surface of the roll-over. From a production standpoint, inserting the segments and aligning them properly around the rim is a time consuming and costly process. Further, once the segments are glued, making sure they remain in place until the glue has set has also been a long standing manufacturing challenge.
Past speaker rings have been formed with lap joint type mating surfaces as shown in FIG. 1. In this arrangement, segments 10 are formed having "L" shaped projections 12 extending from each end of the segment such that when adjacent segments are placed end to end the projections 12 overlap one another. While the lap joint arrangement provides some benefit in helping to properly locate ring segments adjacent one another, it still allows some margin for error in aligning the various segments as shown in FIGS. 1b and 1c. As is clear from these drawings, the lap joint arrangement does not prevent the speaker ring segments from collapsing radially inward toward the center of the speaker. Thus, prior to the glue setting, the segments are somewhat unstable and likely to move. If the glue sets while speaker ring segments are misaligned, the entire assembly must be scrapped.
Therefore, a self aligning segmented speaker ring is desired wherein adjacent abutting segments are automatically centered relative to one another by action of their respective mating surfaces. It is further desired that the mating surfaces provide additional support for maintaining the proper shape of the ring during the period of the assembly process when the glue applied to the speaker ring segments is setting.